The invention relates to an air guide housing for a heating or air conditioning unit for motor vehicles, which housing is disposed in the driver and passenger foot region in the middle of the vehicle under the windshield and which includes controllable openings for the distribution of fresh or heated air to the region of the windshield and the passenger foot region. The invention is especially related to arrangements of this kind which include outlet nozzles and which is formed with two housing parts at opposite sides of a separation plane extending in the vehicle longitudinal direction and which includes a foot level housing part extending transverse to the separating plane and which is connected together as a separate part to the other two housing parts.
There are known heating and air conditioning devices for motor vehicles (DE-PS No. 2437232), where a housing, usually formed out of plastic material, is arranged in the region of the vehicle center tunnel (longitudinally extending centrally disposed tunnel or hump for accomodating the drive shaft and the like) and from which the fresh or heated air is selectively directed toward the windshield or the side windows, as well as to the foot space for the driver and the adjacent passenger. Known housings of this kind are configured in two parts and are connected at a transverse separating plane. In such prior arrangements, the necessary or desired heat exchange aparatus and air guide flaps and the like are selected and inserted in the housing parts for the corresponding vehicle type prior to assembly of the housing parts to form a complete air guide housing. Because of the relatively complicated form of such prior housing parts, the manufacturing costs are very large especially under the circumstances where different forms and parts are required for each different vehicle type. A further disadvantage of such prior construction is that a single part manufacture of a foot level air housing part is not feasible in part because of the required entry of work tools for undercutting to accomodate foot level side air outlets or nozzles and the like. For these reasons, there have been air guide housings proposed wherein the foot level air outlet nozzles are separate and must later be attached at the assembled housing, sometimes involving clipping on of several nozzles at corresponding housing openings and sometimes also requiring special assembly techniques, such as gluing connections. For the necessary mass production involved in the construction of motor vehicles, this kind of assembly is too expensive.
The invention of this application is based upon the provision to so construct an air guide housing of the type referred to above that no subsequent assembly work is necessary. The invention comprises forming the housing section for the foot level air nozzles as a single construction housing part which extends over both upper housing parts or halves (upperhousing parts disposed at opposite lateral sides of a longitudinally extended separation plane) which is form fitted to the respective upper housing parts by way of connecting guides extending from the separating plane at which the upper housing are interengageably connected to one another. This arrangement exhibits the great advantage that the foot level outlet nozzles are already integrated with the foot level housing parts during assembly of the housing so that, without the need for additional tools, the connection together of the two upper housing parts is done together with the secure and rigid connection of also the foot level outlet housing part. The invention is based upon the idea that, without further necessary manufacturing steps, the connection of the upper housing parts and the lower housing part can be accomplished simultaneously with a sliding together of the upper housing parts at the lower housing part. Thus the lower foot level air outlet housing part is effectively used to form slide guides extending transverse to the separating plane for the form fitting sliding connection of the upper housing parts together with one another and with the lower housing part. With a corresponding configuration of the end connections at the housing parts, the foot level air outlets are supportingly fixed in position upon the connection of the housing parts.
In particularly preferred embodiments of the invention, connection fittings are advantageously provided on the respective ends of the upper housing parts opposite the separating plane. It is possible in this manner to obtain an arrangement with closed or partly open outlet openings for the foot level air outlet housing parts in these end regions. Because of the manner of the assembly, the form of the foot level outlet nozzles and the form of the foot level housing part can be chosen independently of the outward form of the upper housing parts. This means that the cross section and the outer form of the foot level housing part can be independent of the respective design requirements of the remainder of the housing. It is for example advantageous and possible to permit the free cross section inside of the foot level outlet housing part to continuously increase toward the air outlet openings, so that a kind of "diffuser" effect results. On the other hand one can form the lower housing part in the middle of the separating plane (middle of the assembled housing) with a curved configuration with respect to the vehicle floor so that the lower housing part extends like a saddle over the region of a vehicle middle "hump" or tunnel. In that way, the necessary construction room for the air guide housing of the heater and/or air conditioner can be made smaller without however influencing the efficiency of the desired air flow in the region of the floor.
According to especially preferred embodiments, the sliding guide at the corresponding connecting walls of the upper housing parts are provided so that they extend somewhat parallel to one another and grip into corresponding sliding grooves on the upper corners of the lower foot level housing parts. The sliding guides of the housing parts can advantageously converge slightly conically toward the separating plane, which results in the advantage that during the manufacture of the upper housing parts the formation of the outward form is not hindered. Also, for the later guidance of these guides in the slots or grooves, the danger of clamping or binding of the front sides of the sliding connection is reduced. The sliding grooves at the lower housing parts can additionally be formed to diverge in a tunnel like form at the insert side, so that the already simple assembly of the upper housing parts with the lower housing parts is further simplified. Since the housing parts are held together by means of interengaging parts, the assembly of the new housing according to this invention requires no work tools.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a single embodiment in accordance with the present invention.